Ink jet technology represents a means of achieving quiet, high speed, high quality, all-points-addressable printing. These attributes make it an attractive candidate compared to other printing technologies. The primary limitations of synchronous ink jet technology and the servo systems that have been developed to maintain the ink jet operating point within these limits are fully described in the literature.
The servoing--or reservoing--of ink jet printers is well known in the art. The application incorporated by reference describes the determination of the print window, which includes setting to their optimum values the crystal drive, the ink stream velocity, and the phase of charge electrode signals.
In the prior art, reservoing was performed periodically, a common fixed period between reservoings being about 40 minutes. In some cases, reservoing is not performed until there is a visible degradation in the quality of prints. In a system using a multinozzle ink jet head, reservoing can require up to 20 seconds, even when using automatic techniques as described in the literature.